The first ever attack of wheat blast in Bangladesh cost the country a financial loss of at least Tk 1,800 crore in terms of lost yield this year.

Caused by a fungus - Magnaporthe oryzae - wheat blast is one of the most fearsome and intractable wheat diseases in recent decades, according to the International Maize and Wheat Research Center (CIMMYT).

Hitherto mostly confined within the continent of South America, the disease's attack in Bangladeshi wheat fields this season is the first case of wheat blast in Asia. The blast directly strikes the ears of wheat and can shrivel and deform the grain in less than a week from first symptoms, leaving farmers no time to act.

The blast affected 1,08,715 hectares of wheat fields in the districts of Jessore, Kushtia, Chuadanga, Meherpur, Jhenidah, Magura, Barisal and Bhola, causing up to 40 percent of crop damage.

Following the maiden blast attack in the wheat fields of mostly southwestern districts in February-March, the government formed a national committee in late March to map out a future course of action to stop recurrence of the deadly disease.

The country's preeminent plant pathologist Prof Dr M Bahadur Meah heads the committee that has representatives from the United Nations Food and Agriculture Organisation (FAO), research institutions concerned, scientists, academics and experts.

At the most conservative estimate, said Dr Bahadur Meah, "We were expecting a minimum yield of 2,17,430 tonnes of wheat from the affected areas. Our estimate now shows that up to 40 percent yield worth Tk 1,826 crore is lost to the blast."

To assess the severity of the wheat blast and the extent of loss incurred, he along with some other experts has visited as many as 39 fields in eight districts in recent weeks.

Prof Bahadur, who teaches plant pathology at Bangladesh Agricultural University,

Mymensingh, is now at an advanced stage of charting out an immediate course of action to deal with the blast, which first emerged in Brazil in 1985.

He said the experts have already advised the government not to source seeds from any of these affected districts for distribution among farmers in next wheat season (November-December).

"Besides, we're strongly recommending treating all seeds with fungicides and testing seed health at seed pathology labs by collecting samples both from BADC stock and also from seeds saved by farmers," he added.

Bangladeshi wheat growers require more than 60,000 tonnes of seeds a year - one-third of which is supplied by the state-run Bangladesh Agriculture Development Corporation (BADC), while the rest comes from farmers' own-saved stocks.

Farmers all over the country cultivated wheat in 4.3 lakh hectares of land in 2015-16 season with a yield projection of 1.3 million tonnes. To bridge a huge demandsupply gap in domestic market, the public and private sectors together import more than 3.5 million tonnes ofwheat each year.

Mexico-based CIMMYT, the world’s premier wheat and maize research organisation, states in one of its most recent priority briefing, "The consequences of a wider outbreak in South Asia could be devastating to a region of 300 million undernourished people, whose inhabitants consume over 100 million tonnes of wheat each year."

Dr Moin U Salam, principal research officer at the Department of Agriculture and Food, Western

Australia (DAFWA), has the experience of playing a role in tackling attacks of yellow rust in wheat in Australia in 2004-05.

"I can tell you from my experience that Bangladesh must make sure no seeds are taken from this year’s blast-affected region for sowing in next wheat season. All seeds have to be chemically treated before sowing" Dr Salam, also an ex-faculty of Bangladesh Agricultural University, told The Daily Star.

He suggests a fungicide application in late January in the wheat fields as a preventive measure "because you can't do anything about it once the blast strikes already."

Tofazzal Islam, an ecological chemist and head of the biotechnol -ogy department of Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), puts emphasis on validating fungi-cide/s, which would be most effective to treat seeds or for subsequent sprays du ring next wheat growingseason.

Upon alerted by a report of The Daily Star on wheat blast in the beginning of March, Tofazzal teamed up with The Sainsbury Laboratory led by Sophien Kamoun and The Genome Analysis Centre (TGAC) led by Diane Saunders to float a collaboration - called OpenWheatBlast - dedicated to work on blast attacks in Bangladesh’s wheat fields.

Tofazzal as well as Wais Kabir, a FAO consultant, said vigorous research needs to be pursued in development of blast-resistant wheat varieties.

Naresh Chandra Deb Barma, director of the country's lone public sector Wheat Research Centre (WRC) in Dinajpur, told The Daily